WIP3

Author: ryancheung

src/FontStashSharp/FontAtlas.cs

@@ -2,7 +2,7 @@
 using FontStashSharp.Rasterizers.FreeType;
 using Microsoft.Xna.Framework;
 using Microsoft.Xna.Framework.Graphics;
-
+using FreeTypeSharp;
 
 namespace FontStashSharp
 {
@@ -168,6 +168,16 @@ public void RenderGlyph(GraphicsDevice graphicsDevice, DynamicFontGlyph glyph, F
 				return;
 			}
 
+			fontSource.RasterizeGlyphBitmap(glyph.Id, glyph.FontSize, fontStyle);
+
+			if (fontStyle.HasFlag(FontStyle.Italic) && !fontSource.HasStyleFlag(FT_STYLE_FLAG.FT_STYLE_FLAG_ITALIC))
+			{
+				fontSource.GetCurrentGlyph(out var glyphRec);
+				// Set new advance and size for italic glyph
+				glyph.XAdvance = (int)glyphRec.advance.x >> 6;
+				glyph.Size = new Point((int)glyphRec.bitmap.width, (int)glyphRec.bitmap.rows);
+			}
+
 			const int cBytesPerPixel = 4;
 
 			// Render glyph to pixel buffer(rgba32)
@@ -210,7 +220,7 @@ public void RenderGlyph(GraphicsDevice graphicsDevice, DynamicFontGlyph glyph, F
 
 			Texture2DManager.SetTextureData(Texture, eraseArea, _eraseBuffer);
 
-			fontSource.RasterizeGlyphBitmap(glyph.Id,
+			fontSource.FetchGlyphBitmapBuffer(glyph.Id,
 				glyph.FontSize,
 				pixelBuffer,
 				0,

src/FontStashSharp/Rasterizers/FreeTypeSource.cs

@@ -102,7 +102,7 @@ private void LoadGlyph(int glyphId)
 				throw new FreeTypeException(err);
 		}
 
-		private void GetCurrentGlyph(out FT_GlyphSlotRec_ glyph)
+		public void GetCurrentGlyph(out FT_GlyphSlotRec_ glyph)
 		{
 			glyph = Marshal.PtrToStructure<FT_GlyphSlotRec_>((IntPtr)_faceRec->glyph);
 		}
@@ -137,30 +137,8 @@ static byte LuminanceFromLinearRGB(byte r, byte g, byte b)
 			// Y = 0.2126*R + 0.7152*G + 0.0722*B. Computed on the integer pipe.
 			return (byte)((4732UL * r + 46871UL * g + 13933UL * b) >> 16);
 		}
-		public unsafe void RasterizeGlyphBitmap(int glyphId, float fontSize, byte[] buffer, int startIndex, int outWidth, int outHeight, int outStride, FontStyle fontStyle)
+		public void FetchGlyphBitmapBuffer(int glyphId, float fontSize, byte[] buffer, int startIndex, int outWidth, int outHeight, int outStride, FontStyle fontStyle)
 		{
-			SetPixelSizes(0, fontSize);
-			LoadGlyph(glyphId);
-
-			FT_Render_Glyph(_faceRec->glyph, _renderMode);
-
-			if ((fontStyle & FontStyle.Bold) != 0 && (_faceRec->style_flags & (int)FT_STYLE_FLAG.FT_STYLE_FLAG_BOLD) == 0)
-				FT_Bitmap_Embolden(_libraryHandle, &_faceRec->glyph->bitmap, 64, 0);
-
-			if ((fontStyle & FontStyle.Italic) != 0 && (_faceRec->style_flags & (int)FT_STYLE_FLAG.FT_STYLE_FLAG_ITALIC) == 0)
-			{
-				FT_Matrix_ italicMatrix = new FT_Matrix_
-				{
-					xx = 0x10000,
-					xy = (nint)(0.3f * 0x10000),
-					yx = 0,
-					yy = 0x10000
-				};
-				FT_Set_Transform(_faceRec, &italicMatrix, default);
-			}
-			else
-				FT_Set_Transform(_faceRec, default, default);
-
 			FT_GlyphSlotRec_ glyph;
 			GetCurrentGlyph(out glyph);
 			var ftbmp = glyph.bitmap;
@@ -229,5 +207,36 @@ public unsafe void RasterizeGlyphBitmap(int glyphId, float fontSize, byte[] buff
 				}
 			}
 		}
+
+		public void RasterizeGlyphBitmap(int glyphId, float fontSize, FontStyle fontStyle)
+		{
+			SetPixelSizes(0, fontSize);
+
+			if ((fontStyle & FontStyle.Italic) != 0 && (_faceRec->style_flags & (int)FT_STYLE_FLAG.FT_STYLE_FLAG_ITALIC) == 0)
+			{
+				FT_Matrix_ italicMatrix = new FT_Matrix_
+				{
+					xx = 0x10000,
+					xy = (nint)(0.3f * 0x10000),
+					yx = 0,
+					yy = 0x10000
+				};
+				FT_Set_Transform(_faceRec, &italicMatrix, default);
+			}
+			else
+				FT_Set_Transform(_faceRec, default, default);
+
+			LoadGlyph(glyphId);
+
+			FT_Render_Glyph(_faceRec->glyph, _renderMode);
+
+			if ((fontStyle & FontStyle.Bold) != 0 && !HasStyleFlag(FT_STYLE_FLAG.FT_STYLE_FLAG_BOLD))
+				FT_Bitmap_Embolden(_libraryHandle, &_faceRec->glyph->bitmap, 64, 0); // 1Pixel embolden
+		}
+
+		public bool HasStyleFlag(FT_STYLE_FLAG flag)
+		{
+			return (_faceRec->style_flags & (int)flag) != 0;
+		}
 	}
 }